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1.
利用广东省乐昌高山气象站1972—1978年观冰资料和气候资料,分析了粤北地区导线覆冰的气象特征,建立了导线覆冰标准冰厚的气象推算模型。根据乐昌国家气象站的历史资料,对乐昌高山气象站的气候资料进行订正延长,构建了乐昌高山气象站覆冰年极值长年代序列,并推算出离地不同高度各重现期的标准冰厚值。结果表明,粤北地区导线覆冰主要发生在1月,其次为2月和12月,平均覆冰期在90天左右,最长覆冰期可达131天以上。主导风向、日最低气温、日降水量是影响导线覆冰厚度的主要气象因素。标准冰厚的年极值序列服从极值I型概率分布,历史上的最大导线覆冰值出现在2008年1月26日,2m高度标准冰厚达64.4mm,15m高度标准冰厚达92.7mm,与2008年冰灾实况调查的覆冰厚度(标准冰厚)115mm较为接近。 相似文献
2.
基于逐步多元线性回归和人工神经网络两种方法,利用安徽省有电线积冰观测的15个气象台站建站至2008年的观测资料,建立了安徽省3个不同区域电线积冰标准冰厚的气象估算模型。结果表明:相比人工神经网络模型,逐步多元线性回归模型预测效果较好;在覆冰机理认识上,印证了影响标准冰厚主要是气温、湿度和风速3个因子的配置,其中气温是影响覆冰的最重要因子;平原和丘陵地区的标准冰厚受当日气象条件影响更多,而高山地区与前几日及当日的气象条件均密切相关,且26个气象因子 (1987—2008年资料) 构建的模型的预测效果好于24个气象因子长序列 (建站—2008年资料) 效果。最后利用最优模型推算各区域非观冰站电线积冰标准冰厚,为冰冻灾害的评估以及风险区划的开展提供了基础。 相似文献
3.
利用安徽省82个气象观测站自建站至2018年2月雨凇、雾凇、混合淞日数,15个观冰站覆冰厚度和海拔高度数据,通过建立覆冰厚度与凇日数之间的关系,推算安徽省82个测站30 a、50 a和100 a一遇的标准冰厚,最后利用地形对标准冰厚进行订正。结果表明:安徽省各重现期下的标准冰厚与雨凇、雾凇和混合凇总日数具有显著的正相关关系;海拔高度与各重现期下标准冰厚呈指数关系;对海拔高于100 m的地区利用海拔高度对标准冰厚进行订正,可得到更为合理的安徽省各重现期下标准冰厚空间分布。 相似文献
4.
《高原气象》2017,(1)
运用线性回归、小波分析等方法,对中国中东部3个高山气象站(南岳、庐山和黄山)平均风速、气温和降水的气候变化特征进行了对比分析,结果表明:(1)3个站年平均风速均呈明显减小趋势,3个站在20世纪60年代末期之后时间变化特征相似。(2)3个站年最大小时风速在20世纪60年代明显减小,之前最大小时风速较大,变化趋势不明显,之后最大小时风速明显减小,且呈显著减小趋势。(3)3个站的风向均存在明显的季节转换,夏半年盛行偏南风,冬半年盛行偏北风。南岳站和庐山站风速呈现"春夏大、秋冬小",黄山站呈现"秋季小、春夏冬大"。3个站平均风速有比较一致的2~3年、5~7年周期变化,在大周期略有不同。(4)3个站气温均呈明显上升趋势,存在2~3年、5~7年和准15年左右的振荡周期。(5)3个站降水量均呈不显著上升趋势,雨日数在南岳站和庐山站呈显著下降趋势,在黄山站呈显著上升趋势。3个站降水量有比较一致的2~3、5~7年左右的周期变化,在大周期变化有所不同;雨日有比较一致的2~3年、4~7年、准10年周期变化,在大周期变化有所不同。 相似文献
5.
《湖北气象》2015,(3)
利利用1960—2011年湖北省81个气象站气象观测资料和湖北省2004—2012年220~500 k V高压输电线路覆冰事故资料以及海拔高度、坡度、坡向等9类地形数据信息资料,给出风口、突出山体、迎风坡和背风坡4种特殊地形的判断指标,分析特殊地形因子对电线覆冰的影响,并对湖北省冰区分布图进行地形订正。结果表明:风口判断指标为冬季(当年12月至翌年2月)日均风速大于8 m·s-1的日数超过1.56 d·a-1,迎风坡判断指标为坡向0°~45°或315°~360°且坡度大于10°,背风坡判断指标为坡向135°~225°且坡度大于10°,突出山体判断指标为起伏度大于200 m且海拔高度大于起伏度;4种特殊地形下冰厚订正系数分别为1.75、1.62、0.68和1.82;风口处影响覆冰的主导气象因子为风速,迎风坡处影响覆冰的主导气象因子为降水量,突出山体处影响覆冰的主导气象因子为液水含量,气温对3种特殊地形下的冰厚变化均有显著影响;经过地形订正后的冰区图,能更好地反映鄂西南山区、鄂北中部和西部等地受特殊地形影响而出现的较严重覆冰区。 相似文献
6.
在总结分析导线覆冰模型理论框架及其影响导线覆冰增长强度的主要气象因子的基础上,根据四川省二郎山观冰站2006年1月—2009年3月的覆冰观测资料和同期常规气象资料,分析发现覆冰密度仅与气温相关显著,运用非线性回归分析建立了导线覆冰密度模型;利用能见度与液态水含量的转换关系估算了空气中的液态水含量及其输送指标,在此基础上建立了一个以气温、风速等常规气象观测要素为参数的导线覆冰模型,以便于工程应用。对模型拟合结果进行分析,实测冰厚和拟合冰厚之间的相关系数为0.8340,拟合冰厚的均方根误差为28.61 mm。 相似文献
7.
利用常规气象资料建立的导线覆冰模型 总被引：1，自引：1，他引：0
利用2001-2009年冬季四川省二郎山观冰站的覆冰资料和气象资料,在明确影响导线覆冰因子及建立覆冰模型理论框架的基础上,分析了覆冰厚度与若干气象因子的联系,结果发现覆冰增长与水汽压、风速等单一气象指标之间的相关并不理想;尝试用若干气象指标综合咸水汽输送量指标,该指标与覆冰增长率有较显著的相关。在此基础上建立了一个以风速、温度、水汽压等常规气象观测要素为参数的导线覆冰模型,将综合覆冰拟合的冰厚与实测冰厚值进行比较,拟合结果较好地模拟了实际覆冰,达到工程应用的目的。 相似文献
8.
中国冰冻天气的气候特征 总被引：8，自引：0，他引：8
研究冰冻天气的空间分布和变化规律对于冰冻灾害的预测、预估以及防灾减灾具有重要意义。利用1961—2008年603个站点雾凇和雨凇天气现象资料,283个站点的电线覆冰资料,采用计算多年平均值、标准冰厚转换、EOF以及求趋势变化等方法,研究了我国冰冻天气的空间分布和气候变化特征。结果表明:全国大部分地区都有冰冻天气出现;雾凇主要出现在北方地区,雨凇主要出现在南方。年冰冻日数随海拔高度增加而增加,但海拔3100 m高度以上冰冻日数较少。冰冻厚度较大的地区位于东北东南部、华北东部、西北地区东南部、西南地区东部、江南东北部。在全球气候变暖背景下,我国大部分地区冰冻天气发生频次减少,但强度增强。 相似文献
9.
利用山西省18个积冰站电线积冰观测资料和91个气象站常规观测资料,采用逐步回归分析方法,针对不同气候区分别构建电线覆冰设计冰厚的气象估算模型,推算各站30 a、50 a、100 a重现期下的设计冰厚。在此基础上,结合DEM数据和电网运行覆冰观测资料,对设计冰厚进行地形订正和易冰区微地形运行经验修正,最终得到山西省电网电线覆冰厚度空间分布及区划结果。结果表明:(1)山西省电线覆冰的设计冰厚整体与气温、相对湿度、风速、水汽压等密切相关,其中高山区的设计冰厚还与降水量、日照时数关系密切,且受连续3 d的气象条件影响,而丘陵和平原区则与当日和前一日或前二日的气象条件密切相关;(2)构建的分区设计冰厚气象估算模型对各气候区的覆冰厚度模拟效果较好,估算偏差五台山前约2 mm,其余地区小于1.2 mm;(3)地形订正后的结果更为合理地反映山西省各重现期下电线覆冰厚度的空间特征,即覆冰厚度随纬度降低而减小,中、重冰区主要分布在恒山、五台山、管涔山、吕梁山、太岳山和太行山等高海拔地区,而沿黄河一带和盆地为轻冰区,且盆地覆冰最轻;(4)易覆冰区经运行经验修正后,其覆冰厚度能够更加精确表达局部微地形区覆冰真实情况,这对电力部门具有实际参考价值。 相似文献
10.
利用WRF模式和Jones电线积冰模型对发生在2010年2月10—11日湖北地区的电线覆冰舞动事故的天气过程进行分析,并对灾害性天气的可预报性进行初步探讨。结果表明:Jones电线积冰模型基于观测降水数据计算积冰厚度在1.3~5.4mm,与观测量级相同。由于WRF模式对此次天气过程的降水量模拟偏大而高估了电线积冰厚度。WRF模式模拟的10m风速风向与观测的一致性较好,模拟本次过程的风速为5~10m·s-1,风向为偏北风,而湖北地区输电线路以东西走向为主,较容易发生舞动事故。 相似文献
11.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d. 相似文献
12.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region. 相似文献
13.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms. 相似文献
14.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics. 相似文献
15.
《大气和海洋科学快报》2013,(1):67
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted 相似文献
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<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea. 相似文献
18.
《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
20.
《大气和海洋科学快报》2012,(3):273
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences 相似文献